The Château de Plieux, a fortified castle on a hilltop in the Gascony region of southwestern France, overlooks rolling fields speckled with copses and farmhouses. A tricolor flag snaps above the worn beige stone. The northwest tower, which was built in the fourteenth century, offers an ideal position from which to survey invading hordes. Inside the château’s cavernous second-story study, at a desk heavy with books, the seventy-one-year-old owner of the property, Renaud Camus, sits at an iMac and tweets dire warnings about Europe’s demographic doom.

On the sweltering June afternoon that I visited the castle, Camus—no relation to Albert—wore a tan summer suit and a tie. Several painted self-portraits hung in the study, multiplying his blue-eyed gaze. Camus has spent most of his career as a critic, novelist, diarist, and travel essayist. The only one of his hundred or so books to be translated into English, “Tricks” (1979), announces itself as “a sexual odyssey—man-to-man,” and includes a foreword by Roland Barthes. The book describes polyglot assignations from Milan to the Bronx. Allen Ginsberg said of it, “Camus’s world is completely that of a new urban homosexual; at ease in half a dozen countries.”

In recent years, though, Camus’s name has been associated less with erotica than with a single poignant phrase, le grand remplacement. In 2012, he made this the title of an alarmist book. Native “white” Europeans, he argues, are being reverse-colonized by black and brown immigrants, who are flooding the Continent in what amounts to an extinction-level event. “The great replacement is very simple,” he has said. “You have one people, and in the space of a generation you have a different people.” The specific identity of the replacement population, he suggests, is of less importance than the act of replacement itself. “Individuals, yes, can join a people, integrate with it, assimilate to it,” he writes in the book. “But peoples, civilizations, religions—and especially when these religions are themselves civilizations, types of society, almost States—cannot and cannot even want to . . . blend into other peoples, other civilizations.”

Camus believes that all Western countries are faced with varying degrees of “ethnic and civilizational substitution.” He points to the increasing prevalence of Spanish, and other foreign languages, in the United States as evidence of the same phenomenon. Although his arguments are scarcely available in translation, they have been picked up by right-wing and white-nationalist circles throughout the English-speaking world. In July, Lauren Southern, the Canadian alt-right Internet personality, posted, on YouTube, a video titled “The Great Replacement”; it has received more than a quarter of a million views. On great-replacement.com, a Web site maintained anonymously, the introductory text declares, “The same term can be applied to many other European peoples both in Europe and abroad . . . where the same policy of mass immigration of non-European people poses a demographic threat. Of all the different races of people on this planet, only the European races are facing the possibility of extinction in a relatively near future.” The site announces its mission as “spreading awareness” of Camus’s term, which, the site’s author concludes, is more palatable than a similar concept, “white genocide.” (A search for that phrase on YouTube yields more than fifty thousand videos.)

“I don’t have any genetic conception of races,” Camus told me. “I don’t use the word ‘superior.’ ” He insisted that he would feel equally sad if Japanese culture or “African culture” were to disappear because of immigration.

Camus’s partner arrived in the study with a silver platter, and offered fruitcake and coffee. Camus, meanwhile, told me about his “red-pill moment”—an alt-right term, derived from a scene in the film “The Matrix,” for the decision to become politically enlightened. As a child, he said, he was a “xenophile,” who was delighted to see foreign tourists flocking to the thermal baths near his home, in the Auvergne. In the late nineties, he began writing domestic travel books, commissioned by the French government. The work took him to the department of Hérault, whose capital is Montpellier. Although Camus was familiar with France’s heavily black and Arab inner suburbs, or banlieues, and their subsidized urban housing projects, known as cités, his experience in Hérault floored him. Travelling through medieval villages, he said, “you would go to a fountain, six or seven centuries old, and there were all these North African women with veils!” A demographic influx was clearly no longer confined to France’s inner suburbs and industrial regions; it was ubiquitous, and it was transforming the entire country. Camus’s problem was not, as it might be for many French citizens, that the religious symbolism of the veil clashed with some of the country’s most cherished secularist principles; it was that the veil wearers were permanent interlopers in Camus’s homeland. He became obsessed with the diminishing ethnic purity of Western Europe.

Camus supports the staunchly anti-immigrant politician Marine Le Pen. He denied, however, that he was a member of the “extreme right,” saying that he was simply one of many voters who “wanted France to stay French.” In Camus’s view, Emmanuel Macron, the centrist liberal who handily defeated Le Pen in a runoff, is synonymous with the “forces of remplacement.” Macron, he noted acidly, “went to Germany to compliment Mme. Merkel on the marvellous work she did by taking in one million migrants.” Camus derides Macron, a former banker, as a representative of “direct Davos-cracy”—someone who thinks of people as “interchangeable” units within a larger social whole. “This is a very low conception of what being human is,” he said. “People are not just things. They come with their history, their culture, their language, with their looks, with their preferences.” He sees immigration as one aspect of a nefarious global process that renders obsolete everything from cuisine to landscapes. “The very essence of modernity is the fact that everything—and really everything—can be replaced by something else, which is absolutely monstrous,” he said.

Camus takes William F. Buckley, Jr.,’s injunction to stand “athwart history, yelling Stop” to the furthest extent possible, and he can be recklessly unconcerned about backing up his claims. On a recent radio appearance, he took a beating from Hervé le Bras, a director emeritus at the Institut National d’Études Démographiques, who said that Camus’s proclamations about ethnic substitution were based on wildly inflated statistics about the number of foreigners entering France. Afterward, Camus breezily responded on Twitter: “Since when, in history, did a people need ‘science’ to decide whether or not it was invaded and occupied?”

Camus has become one of the most cited figures on the right in France. He is a regular interlocutor of such mainstream intellectuals as Alain Finkielkraut, the conservative Jewish philosopher, who has called Camus “a great writer,” and someone who has “forged an expression that is heard all the time and everywhere.” Camus also has prominent critics: the essayist and novelist Emmanuel Carrère, a longtime friend, has publicly reproached him, writing that “the argument ‘I’m at home here, not you’ ” is incompatible with “globalized justice.” Mark Lilla, the Columbia historian and scholar of the mentality of European reactionaries, described Camus as “a kind of connective tissue between the far right and the respectable right.” Camus can play the role of “respectable” reactionary because his opposition to multicultural globalism is plausibly high-minded, principally aesthetic, even well-mannered—a far cry from the manifest brutality of the skinheads and the tattooed white nationalists who could put into action the xenophobic ideas expressed in “Le Grand Remplacement.” (At a rally in Warsaw on November 11th, white-nationalist demonstrators brandished signs saying “Pray for an Islamic Holocaust” and “Pure Poland, White Poland.”) When I asked Camus whether he considered me—a black American living in Paris with a French wife and a mixed-race daughter—part of the problem, he genially replied, “There is nothing more French than an American in Paris!” He then offered me the use of his castle when he and his partner next went on a vacation.

Although Camus presents his definition of “Frenchness” as reasonable and urbane, it is of a piece with a less benign perspective on ethnicity, Islam, and territory which has circulated in his country for decades. Never the sole preserve of the far right, this view was conveyed most bluntly in a 1959 letter, from Charles de Gaulle to his confidant Alain Peyrefitte, which advocates withdrawal from French Algeria:

It is very good that there are yellow Frenchmen, black Frenchmen, brown Frenchmen. They prove that France is open to all races and that she has a universal mission. But [it is good] on condition that they remain a small minority. Otherwise, France would no longer be France. We are, after all, primarily a European people of the white race, Greek and Latin culture, and the Christian religion.

De Gaulle then declares that Muslims, “with their turbans and djellabahs,” are “not French.” He asks, “Do you believe that the French nation can absorb 10 million Muslims, who tomorrow will be 20 million and the day after 40 million?” If this were to happen, he concludes, “my village would no longer be called Colombey-les-Deux-Églises, but Colombey-les-Deux-Mosquées!”

Such worry about Muslims has been present across Europe at least since the turn of the twentieth century, when the first “guest workers” began arriving from former French colonies and from Turkey. In 1898 in Britain, Winston Churchill warned of “militant Mahommedanism,” and Enoch Powell’s 1968 Rivers of Blood speech alleged that immigration had caused a “total transformation to which there is no parallel in a thousand years of English history.”

Anxiety about immigrants of color has long been present in the United States, especially in states along the Mexican border. This feeling became widespread after 9/11, and has only intensified with subsequent terrorist acts by Islamists, the Great Recession, and the election of the first black President. Meanwhile, white populations across the world are stagnant or dwindling. In recent years, white-nationalist discourse has emerged from the recesses of the Internet into plain sight, permeating the highest reaches of the Trump Administration. Attorney General Jeff Sessions and the White House senior adviser Stephen Miller endorse dramatic reductions in both legal and illegal immigration. The President’s former chief strategist, Steve Bannon, has returned to his post as the executive chairman of the far-right Web site Breitbart. In a 2014 speech at the Vatican, Bannon praised European “forefathers” who kept Islam “out of the world.” President Trump, meanwhile, has made the metaphor of immigrant invasion literal by vowing to build a wall.

In Europe, which in recent years has absorbed millions of migrants fleeing wars in the Middle East or crossing the Mediterranean from Africa, opposition to immigration is less a cohesive ideology than a welter of reactionary ideas and feelings. Xenophobic nationalism can be found on both the left and the right. There is not even unanimity on the superiority of Judeo-Christian culture: some European nationalists express a longing for ancient pagan practices. Anti-immigrant thinkers also cannot agree on a name for their movement. Distrust of multiculturalism and a professed interest in preserving European “purity” is often called “identitarianism,” but many prominent anti-immigrant writers avoid that construction. Camus told me that he refused to play “the game” of identity politics, and added, “Do you think that Louis XIV or La Fontaine or Racine or Châteaubriand would say, ‘I’m identitarian?’ No, they were just French. And I’m just French.”

Shortly after Trump’s Inauguration, Richard Spencer, the thirty-nine-year-old white nationalist who has become the public face of the American alt-right, was sucker-punched by a protester while being interviewed on a street corner in Washington, D.C. A video of the incident went viral, but little attention was paid to what Spencer said on the clip. “I’m not a neo-Nazi,” he declared. “They kind of hate me, actually.” In order to deflect the frequent charge that he is a racist, he defines himself with the very term that Camus rejects: identitarian. The word sidesteps the question of racial superiority and co-opts the left’s inclusive language of diversity and its critique of forced assimilation in order to reclaim the right to difference—for whites.

Identitarianism is a distinctly French innovation. In 1968, in Nice, several dozen far-right activists created the Research and Study Group for European Civilization, better known by its French acronym, GRECE. The think tank eventually began promoting its ideas under the rubric the Nouvelle Droite, or the New Right. One of its founders, and its most influential member, was Alain de Benoist, a hermetic aristocrat and scholar who has written more than a hundred books. In “View from the Right” (1977), Benoist declared that he and other members of GRECE considered “the gradual homogenization of the world, advocated and realized by the two-thousand-year-old discourse of egalitarian ideology, to be an evil.”

The group expressed allegiance to “diversity” and “ethnopluralism”—terms that sound politically correct to American ears but had a different meaning in Benoist’s hands. In “Manifesto for a European Renaissance” (1999), he argued:

The true wealth of the world is first and foremost the diversity of its cultures and peoples. The West’s conversion to universalism has been the main cause of its subsequent attempt to convert the rest of the world: in the past, to its religion (the Crusades); yesterday, to its political principles (colonialism); and today, to its economic and social model (development) or its moral principles (human rights). Undertaken under the aegis of missionaries, armies, and merchants, the Westernization of the planet has represented an imperialist movement fed by the desire to erase all otherness.

From this vantage point, both globalized Communism and globalized capitalism are equally suspect, and a “citizen of the world” is an agent of imperialism. When Benoist writes that “humanity is irreducibly plural” and that “diversity is part of its very essence,” he is not supporting the idea of a melting pot but of diversity in isolation: all Frenchmen in one territory and all Moroccans in another. It is a nostalgic and aestheticized view of the world that shows little interest in the complex economic and political forces that provoke migration. Identitarianism is a lament against change made by people fortunate enough to have been granted, through the arbitrary circumstance of birth, citizenship in a wealthy liberal democracy.

Benoist’s peculiar definition of “diversity” has allowed him to take some unexpected positions. He simultaneously defends a Muslim immigrant’s right to wear the veil and opposes the immigration policies that allowed her to settle in France in the first place. In an e-mail, he told me that immigration constitutes an undeniably negative phenomenon, in part because it turns immigrants into victims, by erasing their roots. He continued, “The destiny of all the peoples of the Third World cannot be to establish themselves in the West.” In an interview in the early nineties with Le Monde, he declared that the best way to show solidarity with immigrants is by increasing trade with the Third World, so that developing countries can become “self-sufficient” enough to dissuade their citizens from seeking better lives elsewhere. These countries, he added, needed to find their own paths forward, and not follow the tyrannizing templates of the World Bank and the I.M.F.

Benoist told me that, in France’s Presidential election, in May, he voted not for Marine Le Pen but for the far-left candidate Jean-Luc Mélenchon, who shares his contempt for global capitalism. Benoist’s writing often echoes left-wing thinkers, especially the Italian Marxist Antonio Gramsci, who wrote of “hegemony”—or the command that a regime can wield over a population by controlling its culture. In “Manifesto for a European Renaissance,” Benoist argues that white Europeans should not just support restrictive immigration policies; they should oppose such diluting ideologies as multiculturalism and globalism, taking seriously “the premise that ideas play a fundamental role in the collective consciousness.” In a similar spirit, Benoist has promoted a gramscisme de droite—cultural opposition to the rampaging forces of Hollywood and multinational corporations. The French, he has said, should retain their unique traditions and not switch to “a diet of hamburgers.”

Despite Benoist’s affinity for some far-left candidates, “Manifesto for a European Renaissance” has become a revered text for the extreme right across Western Europe, in the U.S., and even in Russia. The crackpot Russian philosopher Aleksandr Dugin, who promotes the ethnopluralist doctrine “Eurasianism,” has flown to Paris to meet Benoist. “I consider him to be the foremost intellectual in Europe today,” Dugin told interviewers in 2012. Earlier this year, John Morgan, an editor of Counter-Currents, a white-nationalist publishing house based in San Francisco, posted an online essay about the indebtedness of the American alt-right to European thought. He described Benoist and grece’s achievement as “a towering edifice of thought unparalleled anywhere else on the Right since the Conservative Revolution in Germany of the Weimar era.”

Although Benoist claims not to be affiliated with the alt-right—or even to understand “what Richard Spencer can know or have learned from my thoughts”—he has travelled to Washington, D.C., to speak at the National Policy Institute, a white-nationalist group run by Spencer, and he has sat for long interviews with Jared Taylor, the founder of the virulently white-supremacist magazine American Renaissance. In one exchange, Taylor, who was educated in France, asked Benoist how he saw himself “as different from identitarians.” Benoist responded, “I am aware of race and of the importance of race, but I do not give to it the excessive importance that you do.” He went on, “I am not fighting for the white race. I am not fighting for France. I am fighting for a world view. . . . Immigration is clearly a problem. It gives rise to much social pathologies. But our identity, the identity of the immigrants, all the identities in the world have a common enemy, and this common enemy is the system that destroys identities and differences everywhere. This system is the enemy, not the Other.”

Benoist may not be a dogmatic thinker, but, for white people who want to think explicitly in terms of culture and race, his work provides a lofty intellectual framework. These disciples, instead of calling for an “Islamic holocaust,” can argue that rootedness in one’s homeland matters, and that immigration, miscegenation, and the homogenizing forces of neoliberal market economies collude to obliterate identities that have taken shape over hundreds of years—just as relentless development has decimated the environment. Benoist’s romantic-sounding ideas can be cherry-picked and applied to local political resentments.

The writer Raphaël Glucksmann, a prominent critic of the French far right, told me that such selective appropriations have given Benoist “a huge authority among white nationalists and Fascists everywhere in the world.” Glucksmann recently met me for coffee near his home, which is off the Rue du Faubourg Saint-Denis, one of the most ethnically diverse thoroughfares in Paris. The Nouvelle Droite, Glucksmann argued, adopted a traditionally German, tribal way of conceiving identity, which the Germans themselves abandoned after the Second World War. The Nazi theorist Carl Schmitt argued that “all right is the right of a particular Volk.” In a 1932 essay, “The Concept of the Political,” he posed the question that still defines the right-wing mind-set: Who is a people’s friend, and who is an enemy? For Schmitt, to identify one’s enemies was to identify one’s inner self. In another essay, he wrote, “Tell me who your enemy is, and I’ll tell you who you are.”

The Nouvelle Droite was fractured, in the nineteen-nineties, by disagreements over what constituted the principal enemy of European identity. If the perceived danger was initially what Benoist described as “the ideology of sameness”—what many in France called the “Coca-Colonization” of the world—the growing presence of African and Arab immigrants caused some members of grece to rethink the essence of the conflict.

One of the group’s founders, Guillaume Faye, a journalist with a Ph.D. from Sciences-Po, split off and began releasing explicitly racist books. In a 1998 tract, “Archeofuturism,” he argued, “To be a nationalist today is to assign this concept its original etymological meaning, ‘to defend the native members of a people.’ ” The book, which appeared in English in 2010, argues that “European people” are “under threat” and must become “politically organized for their self-defense.” Faye assures native Frenchmen that their “sub-continental motherland” is “an organic and vital part of the common folk, whose natural and historical territory—whose fortress, I would say—extends from Brest to the Bering Strait.”

Faye, like Renaud Camus, is appalled by the dictates of modern statecraft, which define nationality in legal rather than ethnic terms. The liberal American writer Sasha Polakow-Suransky, in his recent book, “Go Back to Where You Came From: The Backlash Against Immigration and the Fate of Western Democracy,” quotes Camus lamenting that “a veiled woman speaking our language badly, completely ignorant of our culture” could declare that she is just as French as an “indigenous” man who is “passionate for Roman churches, and for the verbal and syntactic delicacies of Montaigne and Rousseau, for Burgundy wines, for Proust, and whose family has lived for generations in the same valley.” What appalls Camus, Polakow-Suransky notes, is that “legally, if she has French nationality, she is completely correct.”

Faye’s work helps to explain the rupture that has emerged in many Western democracies between the mainstream right, which may support strict enforcement of immigration limits but does not inherently object to the presence of Muslims, and the alt-right, which portrays Muslim immigration as an existential threat. In this light, the growing admiration by Western conservatives for the President of Russia, Vladimir Putin, is easier to comprehend. Not only do thinkers like Faye admire Putin as an emblem of proudly heterosexual white masculinity; they fantasize that Russian military might will help create a “Eurosiberian” federation of white ethno-states. “The only hope for salvation in this dark age of ours,” Faye has declared, is “a protected and self-centered continental economic space” that is capable of “curbing the rise of Islam and demographic colonization from Africa and Asia.” In Faye’s 2016 book, “The Colonisation of Europe,” he writes, of Muslims in Europe, “No solution can be found unless a civil war breaks out.”

Such revolutionary right-wing talk has now migrated to America. In 2013, Steve Bannon, while he was turning Breitbart into the far right’s dominant media outlet, described himself as “a Leninist.” The reference didn’t seem like something a Republican voter would say, but it made sense to his intended audience: Bannon was signalling that the alt-right movement was prepared to hijack, or even raze, the state in pursuit of nationalist ends. (Bannon declined my request for an interview.) Richard Spencer told me, “I would say that the alt-right in the United States is radically un-conservative.” Whereas the American conservative movement celebrates “the eternal value of freedom and capitalism and the Constitution,” Spencer said, he and his followers were “willing to use socialism in order to protect our identity.” He added, “Many of the countries that lived under Soviet hegemony are actually far better off, in terms of having a protected identity, than Western Europe or the United States.”

Spencer said that “clearly racialist” writers such as Benoist and Faye were “central influences” on his own thinking as an identitarian. He first discovered the work of Nouvelle Droite figures in the pages of Telos, an American journal of political theory. Most identitarians have a less scholarly bent. In 2002, a right-wing French insurrectionary, Maxime Brunerie, shot at President Jacques Chirac as he rode down the Champs-Élysées; the political group that Brunerie was affiliated with, Unité Radicale, became known as part of the identitaire movement. In 2004, a group known as the Bloc Identitaire became notorious for distributing soup containing pork to the homeless, in order to exclude Muslims and Jews. It was the sort of puerile joke now associated with alt-right pranksters in America such as Milo Yiannopoulos.

Copycat groups began emerging across Europe. In 2009, a Swedish former mining executive, Daniel Friberg, founded, in Denmark, the publishing house Arktos, which is now the world’s largest distributor of far- and alt-right literature. The son of highly educated, left-leaning parents, Friberg grew up in a wealthy suburb of Gothenburg. He embraced right-wing thought after attending a diverse high school, which he described as overrun with crime. In 2016, he told the Daily Beast, “I had been taught to think multiculturalism was great, until I experienced it.”

Few European nations have changed as drastically or as quickly as Sweden. Since 1960, it has added one and a half million immigrants to its population, which is currently just under ten million; a nationalist party, the Sweden Democrats, has become the country’s main opposition group. During this period, Friberg began to devour books on European identity—specifically, those of Benoist and Faye, whose key works impressed him as much as they impressed Richard Spencer. When Friberg launched Arktos, he acquired the rights to books by Benoist and Faye and had them translated into Swedish and English. Spencer told me that Arktos “was a very important development” in the international popularization of far-right identitarian thought.

Whether or not history really is dialectical, it can be tempting to think that decades of liberal supremacy in Europe have helped give rise to the antithesis of liberalism. In Paris, left-wing intellectuals often seem reluctant to acknowledge that the recent arrival of millions of refugees in Europe, many of them impoverished, poses any complications at all. Such blithe cosmopolitanism, especially when it is expressed by people who can easily shelter themselves from the disruptions caused by globalization, can fuel resentment toward both intellectuals and immigrants.

The philosopher Bernard-Henri Lévy, who has long embodied élite opinion on the French left, sometimes falls prey to such rhetoric. A 2015 essay, which attempted to allay fears of a refugee crisis in Europe, portrayed Syrian refugees as uniformly virtuous and adaptable: “They are applicants for freedom, lovers of our promised land, our social model, and our values. They are people who cry out ‘Europe! Europe!’ the way millions of Europeans, arriving a century ago on Ellis Island, learned to sing ‘America the Beautiful.’ ” Instead of making the reasonable argument that relatively few Muslim refugees harbor extremist beliefs, Lévy took an absolutist stance, writing that it was pure “nonsense” to be concerned about an increased risk of terrorism. Too often, Lévy fights racism with sentimentalism.

Lévy recently met with me at his impeccable apartment, in a sanitized neighborhood near the Champs-Élysées. In our conversation, he offered a more modulated view. “I’m not saying that France should have received all two or three million Syrian refugees,” he said. “Of course, there’s a limited space.” But France had involved itself in Syria’s civil war, by giving support to opponents of the regime, and had a responsibility to help people uprooted by it, he said. Recent debates about European identity, he noted, had left out an important concept: hospitality. “Hospitality means that there is a place—real space, scarce, limited—and that in this place you host some people and you extend a hand.” This did not mean that he wanted an end to borders: “France has some borders, a republican tradition, it is a place. But in this place we have the duty to host. You have to hold the two. A place without hosting would be a shrinking republic. Universal welcoming would be another mistake.” A necessary tension is created between “the infinite moral duty of hospitality and the limited political possibility of welcoming.”

When I asked Lévy why the notion of the great replacement had resonated so widely, he dismissed it as a “junk idea.” “The Roman conquest of Gaul was a real modification of the population in France,” he went on. “There was never something like an ethnic French people.” Raphaël Glucksmann made a similar critique of the idea of “pure” Frenchness. He observed, “In 1315, you had an edict from the king who said anybody who walks on the soil of France becomes a franc.” This is true, but there is always a threshold at which a quantitative change becomes qualitative; migration was far less extensive in the Middle Ages than it is today. French liberals can surely make a case for immigration without pretending that nothing has changed: a country that in 1900 was almost uniformly Catholic now has more than six million Muslims.

The liberal historian Patrick Boucheron, the editor of a recent surprise best-seller that highlights foreign influences on French life throughout the ages, told me that he had little patience for people who bemoan the country’s changing demographics. French people who are struggling today, he said, are victims of unfair economic policies, not Muslims, who still make up only ten per cent of the population. Indeed, only a quarter of France’s population is of immigrant origin—a percentage that, according to Boucheron, has remained stable for four decades. Boucheron sees identitarians as manipulators who have succeeded “in convincing the dominated that their problem is French identity.” For Boucheron, it’s not simply that the great replacement is a cruel idea; it’s also false. “When you oppose their figures—when you say that there were Poles and Italians coming to France in the nineteen-thirties—they say, ‘O.K., but they were Christians,’ ” he said. “So you see that behind identity there’s immigration, and behind immigration there’s hatred of Islam. Eventually, it always comes down to that.”

But to deny that recent migration has brought disruptions only helps the identitarians gain traction. A humanitarian crisis has been unfolding in Paris, and it is clearly a novel phenomenon. This summer, more than two thousand African and Middle Eastern migrants were living in street encampments near the Porte de la Chapelle; eventually, the police rounded them up and dispersed them in temporary shelters. “We don’t have enough housing,” the center-right philosopher Pascal Bruckner told me. “The welfare state is at the maximum of its capabilities. We’re broke. And so what we offer to those people is what happens at Porte de la Chapelle.” Many liberals have downplayed the homeless crisis, rather than discuss potential solutions. “We turn a blind eye to this issue, just to look generous,” Bruckner said. At one point in my conversation with Lévy, he flatly declared that France “has no refugees.” Far-right figures, for their part, have relentlessly exploited Paris’s problems on social media, posting inflammatory videos that make it seem like marauding migrants have taken over every street corner.

Jean-Yves Camus, a scholar of the far right in France (and no relation to Renaud Camus), told me that there is a problematic lack of candor in the way that liberals describe today’s unidirectional mass movement of peoples. “It depends what you call Frenchness,” he said. “If you think that traditional France, like we used to see in the nineteen-fifties and sixties, should survive and remain, then certainly it will not survive. This is the truth. So I think we have to admit that, contrary to what Lévy says, there has been a change.”

But what, exactly, does the notion of “traditional France” imply? The France of de Gaulle—or of Racine—differs in many ways from the France of today, not just in ethnic composition. Renaud Camus recently told Vox that white people in France are living “under menace”—victims of an unchecked foreign assault “as much by black Africa as it is by Northern Islamic Africans.” Yet feminism, Starbucks, the smartphone, the L.G.B.T.Q. movement, the global domination of English, EasyJet, Paris’s loss of centrality in Western cultural life—all of these developments have disrupted what it means “to be French.” The problem with identitarianism isn’t simply that it is nostalgic; it’s that it fixates on ethnicity to the exclusion of all else.

The United States is not Western Europe. Not only is America full of immigrants; they are seen as part of what makes America American. Unlike France, the United States has only ever been a nation in the legal sense, even if immigration was long restricted to Europeans, and even if the Founding Fathers organized their country along the bloody basis of what we now tend to understand as white supremacy. The fact remains that, unless you are Native American, it is ludicrous for a resident of the United States to talk about “blood and soil.” And yet the country has nonetheless arrived at a moment when once unmentionable ideas have gone mainstream, and the most important political division is no longer between left and right but between globalist and nationalist.

“The so-called New Right never claimed to change the world,” Alain de Benoist wrote to me. Its goal, he said, “was, rather, to contribute to the intellectual debate, to make known certain themes of reflection and thought.” On that count, it has proved a smashing success. Glucksmann summed up the Nouvelle Droite’s thinking as follows: “Let’s just win the cultural war, and then a leader will come out of it.” The belief that a multicultural society is tantamount to an anti-white society has crept out of French salons and all the way into the Oval Office. The apotheosis of right-wing Gramscism is Donald Trump.

On August 11th, the Unite the Right procession marched through the campus of the University of Virginia. White-supremacist protesters mashed together Nazi and Confederate iconography while chanting variations of Renaud Camus’s grand remplacement credo: “You will not replace us”; “Jews will not replace us.” Few, if any, of these khaki-clad young men had likely heard of Guillaume Faye, Renaud Camus, or Alain de Benoist. They didn’t know that their rhetoric had been imported from France, like some dusty wine. But they didn’t need to. All they had to do was pick up the tiki torches and light them. ♦

An earlier version of this piece quoted a tweet by Renaud Camus. The quote, which was mistranslated, has been deleted.

This article appears in the print edition of the December 4, 2017, issue, with the headline “ ‘You Will Not Replace Us’.”

Thomas Chatterton Williams, a contributing writer for the Times Magazine, is a Holtzbrinck Fellow at the American Academy in Berlin. He is at work on a book about racial identity.